DEVICE AND METHOD FOR GENERATING PARTIAL REPLICA

摘要

PROBLEM TO BE SOLVED: To generate a highly useable replica with a low storage device capacity and a low updating cost. SOLUTION: In a distributed database environment, data obtained by inquiry from clients 11 and 12 to servers 16 and 17 controlling the database are cached in a storage device as a partial replica 15 by means of the partial replica generating device. This partial replica generating device is provided with a processing means grouping inquiry groups consisting of a plurality of inquiry conditions, a processing means finding a set of inquiry conditions for every grouped inquiry condition, and a processing means sorting the inquiry conditions according to a condition overlapping range in the set of the inquiry conditions and setting the effectiveness degree of each of the sorted conditions according to its overlapping frequency. In generating the partial replica, the condition having the higher effectiveness degree is given higher priority to be used as the inquiry condition.